Tank cleaning apparatus



Feb. 18, 964 L. E. MCKIBBEN 3,

TANK CLEANING APPARATUS Filed July 28, 1961 2 Sheets-Sheet l LLOYD E. MC KIBBJEN INVENTU/P HUEENER 8 WORREL A TTOPNEVS BY Feb. 18, 1964 E. MOKIBBEN 3,121,536

TANK CLEANING APPARATUS Filed July 28. 1961 2 Sheets-Sheet 2 ll 50 m 53 x 5 53 M LLOYD E. MC mass/v INVENTOR' HUEBNER a WORREL ATTORNEYS United States Patent M 3,121,536 TANK CLEANING APPARATUS Lloyd E. McKibhen, 4436 Mary, Visalia, Calif. Filed July 28, 1961, Ser. No. 127,636 1 Claim. (or. 239-253) This invention relates to a spray-type apparatus for cleaning internal surfaces of closed receptacles, such as tanks or the like. It particularly relates to a portable sprinkler adapted successively to clean a number of tanks which must be washed frequently and thoroughly, such as those used in the processing of dairy products.

In various branches of the food processing industry, particularly those dealing in dairy foods, cooking vessels, storage and settling tanks, and similar receptacles must be in an extremely sanitary condition prior to use. This necessitates frequent cleansing of the individual tanks, which is time consuming if done manually.

To satisfy the high standards of sanitation of governmental regulatory agencies, most food and drug processors employ tanks and cooking vessels made from stainless steel, which is highly resistant to oxidation and corrosion. Accordingly, in cleaning these receptacles, many processors use washing fluids containing dilute alkaline solutions of varying caustic characteristics. Since the alkaline solutions are hazardous to persons washing such tanks, it is desirable to clean the receptacles by automatic or mechanical methods rather than manual. In addition many of the tanks and other receptacles used in the above industry are of a non-uniform and/ or asymmetrical con figuration and do not lend themselves to an eflicient manual cleaning operation.

Certain tank constructions have previously included a sprinkler-type cleaning head premanently installed within the tank. The cleansing fluid is then discharged through the head from a source of fluid pressure which washes the interior of the tank prior to draining out a discharge port normally provided near the bottom of the tank. This type of construction is not ideal, since the cost of each cleaning head is necessarily duplicated in all of the tank installations. The cleansing fluid is not easily recovered in this type of installation unless extensive fluid conduits are permanently installed between each tank and the source of pressure fluid to form a closed circulatory system. If the fluid is not recovered, an excessive quantity is required, which further increases the cost.

Accordingly, it is an object of the present invention to provide a portable washing apparatus which can be used with any number of tanks requiring frequent internal cleansing.

Another object is to provide tank washing apparatus which may be readily connected and disconnected from a plurality of tanks or other receptacles requiring cleansing.

Another object of the invention is to provide washing apparatus which may be used with tanks of varying con figurations and volumetric capacities.

Another object is to provide apparatus for cleansing the internal surfaces of gravity-drained tanks which can be readily inserted through an opening normally provided in such tanks.

A further object is to provide a unitary cleansing apparatus which includes a. portable source of fluid pressure, a fluid supply conduit, a discharge head, and a fluid recovery conduit.

A further object of the invention is to provide a rotatable sprinkler head which can be retracted to an inoperative position to facilitate its entry into and removal from a tank through a conventional drain port in the tank.

3,121,536 Patented Feb. 18, 1964 A further object of the invention is to provide a sprinkler head with retractable spray arms which are automatically extended to operating positions during fluid discharge.

These, together with other objects, will become more fully apparent upon reference to the following description and accompanying drawings.

In the drawings:

FIG. 1 is a side elevation of a tank showing connected thereto a cleansing apparatus embodying theprinciples of the present invention, portions of the apparatus being shown schematically.

FIG. 2 is a fragmentary view of the tank of FIG. .1 provided with a conventional spigot.

FIG. 3 is a vertical section taken on line 3-3 of FIG. 1.

FIG. 4 is a fragmentary view in vertical section taken on a plane centrally of outer conduit and its connection with the tank and showing the inner conduit in side elevation.

FIG. 5 is a transverse horizontal section taken on line 55 of FIG. 1.

FIG. 6 is a fragmentary front elevation of the inner conduit of FIG. 4 showing the end having a sprinkler head of the present invention mounted thereon. The spray arms of the sprinkler are shown 'by dashed lines in a retracted position.

FIG. 7 is a plan view of the sprinkler of FIG. 6.

FIG. 8 is a side elevation of the sprinkler of FIG. 6.

FIG. 9 is a somewhat enlarged, transverse, vertical section taken on line 99 of FIG. 6.

FIG. 10 is a somewhat enlarged, transverse, horizontal section taken on line 10-10 of FIG. 6.

Illustrated in FIG. 1 is a tank 10 provided with side walls 11 and a bottom wall 12. A closing cover 13 is detachably secured to the top of the tank for removal to admit various substances to the trunk. If the tank is to be used during the processing of any food or drink intended for human consumption, particularly dairy foods, the tank is normally constructed of stainless steel. The tank is provided with a port 14 in one of the walls at a point near the bottom as a means of draining the tank by gravity. Secured to the side wall of the tank is a spigot 15, or other suitable discharge fluid control means. A flange 16 is used detachably to mount the spigot on the tank.

The cleansing apparatus shown in FIG. 1 includes a pump 20 driven by a motor 21 as a portable source of fluid pressure. A flexible inlet conduit 22 is connected to the pump and is secured to the tank 10 by means of a mounting flange 23, substantially identical to the flange 16 used in mounting the spigot or other fluid control normally associated with the tank. Capscrews 24 connected to the side wall 11 of the tank compress an O-ring 25 to form a fluid-tight connection between the inlet conduit 22 and the wall 11, thereby providing communication between the cavity within the tank and the conduit 22 through port 14.

An outlet conduit 30 is connected to the discharge side of the pump 20 to supply fluid under pressure to a sprinkler head 31 shown internally of the tank. A valve 32 interposed the pump and the sprinkler head provides a means to control the flow to the sprinkler. A supply tank 33, or other suitable source of fluid such as hot water, steam, or diluted alkaline solution, is connected to the valve 32 by means of a charging conduit 34. Also connected to the valve is an auxiliary outlet conduit 35 which terminates in a manually controllable spray 36. The valve 32 is of conventional design and is shiftable to a number of positions to establish communication between the supply tank 33 and the sprinkler head 31, or the pump and'the sprinkler head, or between the pump and the manually controllable spray 36. The details of the valve are well-known to'those skilled in the art and, as such, form no part of the present invention.

The relationship of the inlet conduit 22, outlet conduit 30, and mounting flange 23 isbest shown in' FIGS. 3, 4 and 5. The outlet conduit passes through the periphery of the inlet conduit 22 and the two conduits are 'joined, as by welding, at a point adjacent t'o'the end of inlet conduit 22. The outlet conduit 39' is then extended through the port 14, and upon securing the mounting flange 23 to the tank, the port 14 serves as a means of ingress and egress of fluid flowing through both of the conduits;

FIGS; 6' through 10'illustrate the details of the rotatable sprinkler head 31 mounted on the outlet conduit 3:). The conduit 30 terminates in a fluid inlet 40 circumscribed by a radially outwardly extended flange 41. A retaining collar 42' encircles the flange and is provided with a radially inwardly extended portion 43. A thrust washer 44 is interposed the flange 4i and the inwardly extended portion 43 of the retaining collar. The thrust washer is preferably of a bearing material which is chemically inert. An example of such material is polymerized tetraflubrethy'lene, known as Teflon.

The sprinkler head 31 is provided with a fluid chamber 45 which terminates at its lower end in a radial flange 46 adapted to abut flange 4 1. The sprinkler head is secured to the outlet conduit by means of a resilient bail 47 received in radial bores 48" of thecollar 42 and retained in notches ,49 provided in the flange 46. The relative axial and radial dimensions of the flanges 31 and 46 and the connection formed by the collar 42, washer 44, and bail 47 are such as to provide a controlled fluid leakage therethrough during operation. Such a mounting is known as a self-cleaning connection, and is particularly desirable in cleansing apparatus for use in the dairy industry.

, Pivotally mounted in the sprinkler head is a pair of fluid conducting spray arms 50a having a mounting portion 50 rotatably carried in bushings 51 received in suitable bores52 provided in the head. The bushingsSl are also of Teflon or equivalent chemically inert bearing m'aterial of suitable dimensional stability ina hygroscopic and thermally variable environment. A projecting shoulder 53 on each of the arms limits their inward extension, and a snap ring 54 prevents their withdrawal.

The arms have nozzle portions 55 which are angularly inclined with respect to the main portions of the arms so that axially disposed discharge orifices 56 direct fluid outwardly in a tangential direction and upwardly in a desired trajectory. In an inoperative, retracted position, the arms 50a are substantially aligned with the axis of rotation, as shown in the dashed linesof FIG. 6. An upper stop 57 limits their movement in the direction of the inoperative position.

By reason of the reaction force of the fluid as it is discharged from the orifice 56, each spray arm is moved to' an operative position, as shown in solid lines, and restrained from movement past this position by a lower stop 58. It is to be noted that the diametrical dimension of the sprinkler head when in an inoperative position is less than the diametrical dimension of port 14. This permit-s the insertion of the sprinkler head through the port. The particular mounting of the spray arms 59a insure their assuming an operative position upon the flow of fluid under pressure through the sprinkler head. To cleanse the upper portion of the internal surface or" the tank, a plurality of upwardly directed orifices 60 are provided in the top of the sprinkler head. The number of such orifices and their location are predetermined in relation to the configuration or" the tanks with which th cleansing apparatus is to be used.

Operation The operation of the described embodiment of the subject invention is believed to be readily apparent and is briefly summarized at this point. After the contents of the tank 10 have been removed through the spigot 15, the mounting flange 16 for the spigot is removed to permit insertion of the sprinkler head 31 through the port 14 While the spray arms 50a are in a retracted position. The

. flange 23, which is identical in function to flange 16 and loosen the residual film of the substance previously contained in the tank. After filling the tank to a level above the upper limits of the port 14 to prevent cavitation of the pump 20, the valve 32 is positioned to establish communication between the pump and the sprinkler head. Subsequent operation of the motor 21 draws'fiuid through inlet conduit 22' and forces this fiuid through the outlet conduit and through the sprinkler head to be returned to the pump by means of the inclined bottom wall and the inlet conduit 22.

Upon the initial discharge of fluid from the nozzle portions 55 of the spray arms 5011, the arms are rotated downwardly to an operative position abutting the lower stop 58; This rotation is caused by the reaction force of the fluid jet issuing from orifices 56 in the nozzle portions 55 which are tangentially disposed in relation to the mounting portion 59 to produce a sufficient torque. Accordingly, a rotating sprinkler head is provided which has a reduced diametrical dimension, yet is so constructed to provide a sumcient moment arm for the reactive force of a tangentially dh'ected jet of fluid to insure the rotation of the sprinkler head once it has been located inside a" tank. The combined mechanical action of the jet of cleansing fluid, in addition to the particular chemical action of the selected fluid, is normally satisfactory to cleanse the internal surface of the tank without requiring a manual scraping or brushing action.

The external surface of the tank may also be cleaned by the same apparatus by positioning the valve 32 to direct the fluid from pump 2% through the auxiliary outlet conduit 35. The fluid discharge from the manually controlled spray 36 may be used in discharging the cleansing fluid back to the supply tank 33 as well as cleaning the outside of the tank. With cleansing apparatus constructed in accordance with the principles of the invention, the fluid conduits and sprinkler head requirements are kept to a minimum. Since all of the components are normally made of stainless steel, it can be seen that a sanitary, durable and efiicient apparatus results.

Upon the completion of the cleansing operation, the apparatus is removed from the tank by breaking the conmotion between flange 23 and the tank. Removal of the capscr'ews permits the withdrawal of the sprinkler head 31 through port 14. The spray arms 50a fold to a sufficiently retracted position as the head is passed through the port. Accordingly, it can be seen that cleansing apparatus is provided for the internal surface of the tank, the conventional drain port of the tank being used to admit and withdraw the sprinkler head as well as to admit and Withdraw the cleaning fluid.

Although the invention has been herein shown and de scribed in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claim so as to embrace any and all equivalent devices and apparatus.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

In a rotary sprinkler, a sprinkler head having an internal fluid chamber and an admission port in communication with the chamber; a plurality of fluid discharge arms extended outwardly from the head and in communication with said fluid chamber, a fluid coupling adapted to be connected to a source of fluid under pressure; bearing means rotatably supporting the sprinkler head on the fluid coupling about an axis of rotation; said fluid discharge arms having a first inoperative position extended away from said bearing means in a direction along the axis of rotation and a second position extended radially outwardly and upwardly; and stop means carried by the sprinkler head to limit the range of movement between said first and second positions.

References Cited in the file of this patent UNITED STATES PATENTS Glazier Mar. 28, Schmidt Apr. 28, Vossler Sept. 28, Bradshaw Oct. 31, Buckner Dec. 6, Butterworth Dec. 4, Saussure Apr. 29, Jepson Nov. 25, Sak et a1 June 19, Spender Nov. 6, Howard July 10,

FOREIGN PATENTS Great Britain June 27, 

